Spirit Lake Outflow Safety Improvement Project

The Gifford Pinchot National Forest is responsible for operating, maintaining, and repairing the 1.6 mile Spirit Lake tunnel and the engineered channels at Castle and Coldwater Lakes. Constructed in 1985, the tunnel provides the only outflow for Spirit Lake. To address annual tunnel operation in this dynamic volcanic landscape and to contribute to geologic hazard risk reduction to downstream communities, the Forest Service works with federal, state, and local partners.

The Forest Service is currently developing a collaborative strategy to create more sustainable and safer options for long term management of Spirit Lake Outflow to achieve ecological, economic and public safety needs.

  • Current System

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    Learn about the Spirit Lake outflow tunnel that was built for public safety after the Mount St. Helens eruption in 1980.

  • Core Drilling & Intake Gate Repair

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    The Forest Service has released a decision on activities to enhance public safety and protection to communities downstream of Spirit Lake.

  • Spirit Lake Outflow

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    The Forest Service will be engaging stakeholders to develop a long term Spirit Lake Outflow management solution.

  • Science, Maps, Data

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    Review current scientific reports, data, and information about proposed scientific studies at Mount St Helens. Review background studies and the current decision frameworks.

  • Toutle River System

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    Learn how the forest is working towards a collaborative watershed management plan for the health & safety of the Toutle River watershed and affected communities.

  • Multimedia

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    Browse Spirit Lake Outflow Safety Improvement Project photos.

Contact Us

Project Manager: Ryan Cole

Email: ryan.cole@usda.gov

Phone: 360 891-5005